The only phase that the Rival participates in is the 2nd phase. Instead of placing Ranchers, the Rival reveals one Rival Rancher Card. At the start of the phase, shuffle the deck of Rival Rancher Cards and deal out 4 face-down cards above the deck. Set the remaining cards aside without revealing them. If the Rival has the First Player Marker, it takes the first turn of the round. Alternate turns until you are out of Ranchers to assign and the Rival has played all 4 cards.
The Rival performs 3 steps on its turn: